• Journal of the Korean Magnetics Society
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• v.8 no.6
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• pp.335-340
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• 1998

Colossal magnetoresistance $La_{0.67}Ca_{0.33}Mn_{0.99}^{57}Fe_{0.01}O_3$ material has been produced by a metal-salt routed sol-gel process method. Magnetic properties of $La_{0.67}Ca_{0.33}Mn_{0.99}^{57}Fe_{0.01}O_3$ have been studied with x-ray diffraction, Rutherford back-scattering spectroscopy(RBS), vibrating sample magnetometer, and Mossbauer spectroscopy. Crystalline $La_{0.67}Ca_{0.33}Mn_{0.99}^{57}Fe_{0.01}O_3$ was perovskite cubic structure with a lattice parameter $a_0=3.868$\AA$$. And there was no appreciable change in the value of the lattice parameter when a small amount (x=0.01) of iron was added. However, Mossbauer and VSM data indicate the Curie temperature of the $La_{0.67}Ca_{0.33}Mn_{0.99}^{57}Fe_{0.01}O_3$ decreased from 282 to 270 k and also the saturation magnetization from 84 to 81 emu/g at 77 K. Mossbauer spectra of $La_{0.67}Ca_{0.33}Mn_{0.99}^{57}Fe_{0.01}O_3$ have been taken at various temperatures ranging form 4.2 K to room temperature. Analysis of $^{57}Fe$ Mossbauer data in terms of the local configurations of Mn atoms has permitted the influence of the magnetic hyperfine interactions to be monitored. The isomer shifts show that the charge state of all Fe ions are ferric. The magnetoresistance of $La_{0.67}Ca_{0.33}Mn_{0.99}^{57}Fe_{0.01}O_3$ was about 33 % at semiconductor-metal transition temperature $T_{SC-M}=250K$.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.6
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• pp.25-32
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• 2021

In this study, it proposes a mode converter that is relatively easy to implement and can shorten the transmission line length of the final combining port and it was fabricated and tested by applying it to an 8-way spatial combiner. The proposed mode converter converts the signal converted from the doorknob-shaped circular disk connected to the ground into the TM₀₁ mode by opening it in the circular waveguide. The 8-way waveguide spatial combiner is designed and implemented so that 8 signals input from the H-plane are combined in a circular waveguide at the center, and the final combining mode is TM₀₁. The test results confirmed excellent performance with an insertion loss of less than 0.4dB and a combining efficiency of 95% or more. In addition, it was confirmed that it is suitable for high output by calculating the breakdown voltage and discharge threshold power of the new mode conversion structure through electric field analysis. The results confirmed through this study are expected to be applicable to high-power, high-efficiency SSPA in various fields in the future.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.479-495
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• 2021

To improve on the efficient management of forest resources, it is necessary to create a forest soil map, which represents a comprehensive database of forest lands. Although a 1:25,000 scale forest site map has been used in Korea, the need for a large-scale forest soil map with high precision and information on forest lands that is specialized for individual purposes has been identified. Moreover, to keep pace with the advancement in forest management and transition to a digital society, it is essential to develop a method for constructing new forest soil maps that can diversify its use. Therefore, this paper presented a developmental process and used a 1:5,000 scale forest soil map to propose future directions. National maps showing the soil type, depth, and texture were produced based on the survey and analysis of forest soils, followed by the Forest Land Soil Map (1:5,000) Production Standard Manual. Alternatively, forest soil map data were the basis on which various other maps that can be used to prevent and predict forest disasters and evaluate environmental capacities were developed. Accordingly, ways to provide appropriate information to achieve the national forest plan, secure forestry big data, and accomplish sustainable forest management that corresponds to the national development plan are proposed based on results from the current study.

• The Journal of the Acoustical Society of Korea
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• v.40 no.4
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• pp.320-329
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• 2021

In this paper, an empirical model of air bubble size to be applied to an air masker for reduction of underwater radiation noise is presented. The proposed model improves the divergence problem under the low-speed flow condition of the existing model derived using Rayleigh's jet instability model and simple continuity condition by introducing a jet flow velocity of air. The jet flow velocity of air is estimated using the bubble size where the liquid is quiescent. In a medium without flow, the size of the bubble is estimated by an empirical method where bubble formation regime is divided into a laminar-flow range, a transition range, and a turbulent-flow range based on the Reynolds number of the injected air. The proposed bubble size model is confirmed to be in good agreement with the Computational Fluid Dynamics (CFD) analysis result and the experimental results of the existing literature. Using the acoustic inversion method, the air bubble population is estimated from the insertion loss measured during the air injection experiment of the air- masker model in a large cavitation tunnel. The results of the experiments and the bubble size model are compared in the paper.

• (The) Research of the performance art and culture
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• no.20
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• pp.63-94
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• 2010

Research on Gong Ok-jin's choreography and its artistic value is still insufficient in the academia of Korea. Her life cannot be said even or smooth - she was born into an artist family with abundant innate talent and sensitivity, feeling joy and sorrow as a gypsy artist begging for food, facing and overcoming the crisis of her trademark deformed dance during the period when she played the solo performance of Changmugeuk, making a transition to the animal dance and finally to the sick dance getting her health back from the long struggle against disease. Her life, however, has always been an artistic expression and we can know that art has been the consolation and driving force of her life. In the Korean artistic tradition that integrates music, singing and dancing, it is beyond doubt that the third has been rather secondary compared with the first two. In the Changmugeuk, however, Gong Ok-jin focuses on each movement of hers, commensurate with the humorous witticism and the traditional opera of pansori. What is her message in such painstaking movements? She puts gestures ahead of words and continues them, reminding her audience of the meaning of dance and driving it into them. Especially, her deformed dance, unprecedented in choreographic history, is hard to understand if you do not sympathize with Koreans' innermost emotions. If you are to understand it, you should first feel what emotions are in Koreans' mentality to be expressed in the form of choreographic elements and what artistic values they carry. This study, in this context, is to reflect upon the original choreographic form of her Changmugeuk solo and to overview Korean dance's unique emotional values with regard to the way Korean choreographic subject matters and traditions are passed down.

• Korea Real Estate Review
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• v.28 no.4
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• pp.7-22
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• 2018

This study aimed to empirically analyze the factors that influence newlyweds' housing tenure. For this, a questionnaire survey was conducted among newlyweds living nationwide who had been married for 5 years or less and were under the age of 40. The results of the survey were empirically analyzed by applying various variables. With regard to parental financial support among the factors influencing newlyweds' housing tenure, the analysis results showed that the probability of owner occupancy was high among the households with parental financial support than among those with none, and the larger the size of the parental financial support was, the higher the probability that the newlyweds owned the house they were occupying. As for the housing loan variable, it was found that the probability of owner occupancy was high among the newlyweds with a housing loan than among those with none, and the larger the amount of the newlyweds' housing loan was, the higher the probability that they owned the house they were occupying. As opposed to what is generally recognized, however, the survey showed that the higher the ratio of dual earners is, the lower the owner occupancy probability due to the probability of job transition, etc. In addition, it was found that the probability of owner occupancy for the newlyweds living in Seoul was lower than that for the newlyweds living in other regions in South Korea. Accordingly, this study showed that appropriate levels of parental economic indicators should also be reflected in the stable housing support and loan policies for newlyweds in the context that the succession to their parents' fortunes is generalized.

• Cross-Cultural Studies
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• v.45
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• pp.195-218
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• 2016

This paper focuses on the terminology of the dictionary as an encyclopedic element in the Buddhist language. The previous study on Buddhist language can be divided into a philosophical approach to the language itself, a review of the linguistic perspective of a specific monk, and a linguistic examination of the Buddhist language. The linguistic examination of the Buddhist language is further divided into analysis of certain Buddhist scriptures, and a study of vocabulary used throughout the Buddhist sphere. The Buddhist vocabulary in the existing Korean dictionary is found in specialized areas such as name, place name, history, and Buddhism. By advancing the generalized words of the terminologies, the meanings of the terminologies and the general words are described as polysemy. It is possible to identify the degree of transition from terminology to general word depending on the distribution of senses. In the case of Buddhist vocabulary, the usage as a general language and as a Buddhist term was given priority, and vocabulary was also derived from a Buddhist term, although it was described as a general language. If a dictionary is changed according to the language unit it contains, the difference in a Buddhist terminology for each dictionary, and a conflict between the existing academic research result and the prior description, will need to be resolved through the collaboration of religious experts, linguists, and lexicographers.

• Cross-Cultural Studies
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• v.43
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• pp.207-239
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• 2016

The Altai Humanities Belt connecting Siberia to Central Asia is very important to the history of civilization. It had a huge influence on the formation of an ancient civilization in the Korean Peninsula. Therefore, a variety of studies have been carried out in the field of folklore and anthropology as well as archeology. One of these studies is about the oral epic. The oral epic remains in the form of a unique transmission in Korea, but it wasn't that long ago when it was noted as the component of the Altai Humanities Belt. In that context, some epics from Central Asia, Mongolia, and Siberia were introduced to Korea. This preliminary investigation is conducted to introduce the oral epic Olonkho from Yakutia in Siberia to Korean academia. Although it was revealed recently, Olonkho is highly valued. The epic study has been buried from the Western point of view, but Olonkho is expected to provide a global perspective to the field of epic study. Above all, it contains a very significant clue to a new study because the content and the style of performance are considerably different from those of the West. Additionally, the original form is relatively well preserved. In particular, it explains how human thinking and behaviors have changed in the transition from the mythical age to the heroic age. This change appears in the ethnic history of Yakutia, as well as in the formation process for all Altai countries around the 10th century. Therefore, this preliminary investigation will be a foundation to facilitate the translation of the voluminous Olonkho into Korean, and to conduct full-fledged research on it. In particular, it can motivate a study on the differences and similarities in comparison to the tradition of oral epics between Central Asia and the Korean Peninsula. Furthermore, it will serve as a foundation for the formation of the Altai Humanities Belt.

• The Journal of Korean society of community based occupational therapy
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• v.8 no.3
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• pp.1-12
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• 2018

Objective : This study conducted a preliminary study to develop a occupational therapy model focused on improving living functions within the community care system. Methods : From June to July, 2018, the literature on community care was researched, focusing on cases of Japan's Management Tool for Daily Life Performance (MTDLP), Sweden, United Kingdom, Germany and domestic S Elderly Care Centers and I Health Centers. Based on this information, a group of experts developed a occupational therapy model within the community care system. Results : Assessment tools such as occupation-based health promotional table, interest checklist, occupational goals for improving living functions, sheet for evaluation of living functions, survey of daily life time (weekday and weekend), and sheet for transition of living functions were developed to conduct evaluation for occupational therapy. The improving living functions program, analysis of activities based on ICF model, lifestyle redesign program, cognitive exercise therapy, the Lee Silverman Voice Treatment (LSVT), hospice, and home modification were also organized interventions already in place by occupational therapists. Conclusion : This study showed specific measures and models for the implementation of occupational therapy within community care systems. Occupational therapy is positioned as a specialized area that is essential to the client, and we look forward to the use of this model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.268-277
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• 2019

Flight test systems should monitor various conditions in real time during flight tests and take safety measures in an emergency. The importance of ensuring test safety increases in more complicated and wider test environments. Also, due to the transition of wartime operational authority, many guided missile systems must be developed simultaneously. Early deployment and budget reduction by shortening the development and T&E periods are also necessary. Consequently, the risk of flight tests under the circumstance of inefficient test resources is increasing. To address this deficiency, a flight test system model using SysML was proposed in this study. The method of designing and verifying the test system is based on the agile shift left testing methodology of advanced T&E labs and utilizing a system reference model in the aerospace field. Through modeling and simulation analysis, early identification and correction of faults resulting from inconsistent test requirements can mitigate the risk of delays during the T&E phase of flight tests. Also, because the flight test system model was constructed using SysML, it can be applied to test various guided missile systems.